var bigEl = document.querySelectorAll(".big")
var smallEl = document.querySelectorAll(".small")
var smallEl = document.querySelectorAll(".small")
console.log(smallEl)
for(var i = 0;i<bigEl.length;i++){
    bigEl[i].index = i
    bigEl[i].addEventListener("click",function(){
        for(var j = 0;j<smallEl.length;j++){

      
        smallEl[this.index].style.height = "50px"

        }


    })
}

var nav = document.querySelector('.header')
window.onscroll = function () {
 
    if (nav.offsetTop + nav.clientHeight < document.documentElement.scrollTop) {

        nav.classList.add('fixed')
    } else {

        nav.classList.remove('fixed')
    }
}



























